Adding Classes

Hey guys, I just got rfactor yesterday and immediately installed your mod. I'm a huge ALMS fan and I'm blown away by the quality of this mod, great work!

I was curious how I could add a GTC class to the ALMS 09-12 fields by using the PCC07 mod? I have the skins from kodafactory, but how do I add a GTC category to the enduracers menu? I knew how to do stuff like this in GTR2, but being new to rFactor, I'm not sure where to look. Thanks!